But as the Chicago Jazz Festival celebrates its 30th anniversary this week, the event stands at a turning point.

As the oldest of the city-sponsored downtown music festivals (the gospel, blues and country events all followed), the jazz soiree for years has struggled to break out of well-worn habits to create fresh new formats. The question is whether the pace of change has been brisk enough to keep the Chicago Jazz Festival competitive in a rapidly changing music world.

Counterparts such as the Montreal International Jazz Festival and the San Francisco Jazz Festival, for instance, spend fortunes on programming ($10.6 million for Montreal, $1 million for San Francisco).

The Chicago Jazz Festival -- produced by the Mayor's Office of Special Events, which obtains funding from corporate and foundation sponsorships -- musters an almost laughable $250,000.

Squeezing pennies

Yet through sheer ingenuity, the Mayor's Office and the non-profit Jazz Institute of Chicago -- which has programmed the festival since its inception -- squeeze the most out of every penny. Global stars, Chicago icons and emerging players will light up three stages in Grant Park from Friday through Aug. 31. And though the city's perpetually strained coffers long ago shrank a Grant Park gathering that originally stretched seven days, the event's planners in recent years have added prefest concerts in various venues to create a sprawling, seven-day Chicago Jazz Festival Week, starting Monday.

The boldest experiment begins Thursday, when -- for the first time -- the "official" opening night of the Chicago Jazz Festival will unfold not in Symphony Center (where it has occurred in recent years), nor in Grant Park's acoustically challenged, aesthetically inferior Petrillo Music Shell.

Instead, the 30th anniversary opener will move up to the superb Pritzker Pavilion in Millennium Park, where Rollins will play a free, evening-length concert. For those who long have yearned for the Chicago Jazz Festival to evolve beyond the ramshackle environment and dubious production values of the Petrillo Music Shell, the one-night switch to Millennium Park comes as a breath of badly needed fresh air.

"Change is imminent, change is necessary and change is good," says Michael Orlove, a member of the festival's programming committee and a senior programmer in the city's Department of Cultural Affairs, which books Millennium Park.

"Whether the entire festival or part of the festival could have a life at Millennium Park, we would certainly welcome it with open arms."

Not that such a transition would be easy -- or necessarily feasible, say festival planners. Though the Petrillo can host 75,000 people on its lawn, the Pritzker can accommodate about 11,000, which is thousands fewer than the city says attend Jazz Festival events in Grant Park. (It's worth noting that the Chicago Gospel Festival has flourished at Millennium Park since 2005.)

But by presenting Rollins -- perhaps the biggest star in all of jazz -- at Millennium Park, Jazz Festival organizers will be testing conventional wisdom on the supposed necessity of staging events in Grant Park. For if the Pritzker can handle the Rollins crowd, maybe it can handle any jazz event.

"I'm anxious to see what happens," says Jennifer Washington, coordinator of the Chicago Jazz Festival for the Mayor's Office of Special Events.

"I just don't know if moving the fest totally there is totally a possibility for us. We don't fit in that space. Would I like to see more use of that space [for the festival]? Obviously yes."

Rules at Millennium

Still, the festival might have to overcome another hurdle to further embrace Pritzker Pavilion: promotion.

Though the Petrillo Music Shell is festooned with signage from corporations whose advertising dollars help pay for the event, and though Grant Park is crowded with vendor booths that also help underwrite the festival, Millennium Park restricts such uses, Washington says.

"We would just have to find other creative ways to get a [sponsor's] message out," at Millennium Park, says Washington.

Yet the very notion of presenting a 21st Century jazz festival in massive spaces such as Chicago's downtown parks may be anachronistic. In earlier decades, when legends such as Miles Davis, Count Basie, Ella Fitzgerald and Dizzy Gillespie roamed the globe (and played the Chicago Jazz Festival), a huge, one-size-fits-all venue was appropriate.